/**
   This program runs two threads in parallel.
*/
public class ThreadTester
{
   public static void main(String[] args)
   {
      Runnable r1 = new GreetingProducer("Hello, World!");
      Runnable r2 = new GreetingProducer("Goodbye, World!");
      
      Thread t1 = new Thread(r1);
      Thread t2 = new Thread(r2);

      t1.start();
      t2.start();
   }
}